Nithin Bekal

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Value Object

  • values of the instance variables never change once they have been set in the constructor
  • equality is not based on identity
    • two value objects are equal when their values are equal, not necessarily being the same object.
  • this protects from aliasing problems, ie. bugs caused by changing an object is being referred in two different places.

Money is a good example of value object:

a = Money.new(5)
b = Money.new(5)

a == b #=> true